Imagine buying a textbook and finding a tutor tossed in at no extra cost. That's what happened across the country this year to college students whose introductory logic courses used a teaching package co-authored (with the late Jon Barwise, MS '65, PhD '67) by Provost John Etchemendy. Language, Proof and Logic (CSLI Publications, 1999; $43.95) includes software that connects students via the Internet to an interactive teaching system called Grade Grinder.
Here's how it works. Students submit answers for their problem sets, and Grade Grinder reads their work. If it finds mistakes, the automated "tutor" offers hints or points out principles that would lead to the right answers. The advice arrives by e-mail in seconds instead of the week or more it would typically take for human feedback. Students then can correct their work before Grade Grinder forwards a report to the instructor.
For professors, the package is "like having another TA -- for free," observes Selmer Bringsjord, professor at Rensselaer Polytechnic in Troy, N.Y. Benefits go beyond automated grading, says Etchmendy, PhD '82, who developed the package with Stanford's Center for the Study of Language and Information and researchers at the University of Indiana. "We didn't foresee that part of the value of Grade Grinder would be allowing us to centrally analyze common mistakes." He cites a pattern that showed up at Cal State-Northridge last fall. Many students had difficulty when the wording of problems included the "neither . . . nor" construction, most likely because English wasn't their first language. When difficulties like that crop up, Etchemendy and his colleagues can tinker with Grade Grinder's advice.
They don't see their innovation making human instructors obsolete -- rather, it's designed to free professors and students alike from the most tedious aspects of coursework. Etchemendy believes the software could be adapted easily to other science courses.
Grade Grinder has a downside: it relies on e-mail to transmit its massive reports on students' progress to instructors. "I wish I could get this information in a form that could be easily imported into a database," says Professor Tom Burke of the University of South Carolina. Eager to upgrade, Etchemendy says that his team hopes to offer professors access to their data on the web in a compact form by the start of fall quarter.
